M.B.105
(a) In order to contribute to the improvement of air safety, the competent authorities shall participate in a mutual exchange of all necessary information in accordance with Article 72 of Regulation (EU) 2018/1139.
AMC M.B.105(a)
One typical case where the mutual exchange of information is necessary is when an aircraft is transferred inside the EU according to M.A.903. When notified of such a transfer, a competent authority should inform the competent authority where the aircraft will be registered of any known problems with the aircraft being transferred. Furthermore, the competent authority where the aircraft will be registered should ensure that the former competent authority has been properly notified that the aircraft is leaving.
(b) Without prejudice to the competencies of the Member States, in the case of a potential safety threat involving several Member States, the concerned competent authorities shall assist each other in carrying out the necessary oversight action.